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Weathered Mississippi Canyon 252 crude oil ingestion alters cytokine signaling, lowers heterophil:lymphocyte ratio, and induces sickness behavior in zebra finches (Taeniopygia guttata)
2020
Goodchild, Christopher G. | Love, Ashley C. | Krall, Jeffrey B. | DuRant, Sarah E.
The Deepwater Horizon (DWH) oil spill caused an estimated 100,000 bird mortalities. However, mortality estimates are often based on the number of visibly oiled birds and likely underestimate the true damage to avian populations as they do not include toxic effects from crude oil ingestion. Elevated susceptibility to disease has been postulated to be a significant barrier to recovery for birds that have ingested crude oil. Effective defense against pathogens involves integration of physiological and behavioral traits, which are regulated in-part by cytokine signaling pathways. In this study, we tested whether crude oil ingestion altered behavioral and physiological aspects of disease defense in birds. To do so, we used artificially weathered Mississippi Canyon 242 crude oil to orally dose zebra finches (Taeniopygia guttata) with 3.3 mL/kg or 10 mL/kg of crude oil or a control (peanut oil) for 14 days. We measured expression of cytokines (interleukin [IL]-1β, IL-6, IL-10) and proinflammatory pathways (NF-κB, COX-2) in the intestine, liver, and spleen (tissues that exhibit pathology in oil-exposed birds). We also measured heterophil:lymphocyte (H:L) ratio and complement system activity, and video-recorded birds to analyze sickness behavior. Finches that ingested crude oil exhibited tissue-specific changes in cytokine mRNA expression. Proinflammatory cytokine expression decreased in the intestine but increased in the liver and spleen. Birds exposed to crude oil had lower H:L ratios compared to the control on day 14, but there were no differences in complement activity among treatments. Additionally, birds exposed to 10 mL/kg crude oil had reduced activity, indicative of sickness behavior. Our results suggest cytokines play a role in mediating physiological and behavioral responses to crude oil ingestion. Although most avian population damage assessments focus on mortality caused by external oiling, crude oil ingestion may also indirectly affect survival by altering physiological and behavioral traits important for disease defense.
اظهر المزيد [+] اقل [-]Hematological and histological changes from ingestion of Deepwater Horizon crude oil in zebra finches (Taeniopygia guttata)
2021
Fallon, Jesse A. | Goodchild, Christopher | DuRant, Sarah E. | Cecere, Thomas | Sponenberg, D Phillip | Hopkins, William A.
Exposure to crude oil during spill events causes a variety of pathologic effects in birds, including oxidative injury to erythrocytes, which is characterized in some species by the formation of Heinz bodies and subsequent anemia. However, not all species appear to develop Heinz bodies or anemia when exposed to oil, and there are limited controlled experiments that use both light and electron microscopy to evaluate structural changes within erythrocytes following oil exposure. In this study, we orally dosed zebra finches (Taeniopygia guttata) with 3.3 or 10 mL/kg of artificially weathered Deepwater Horizon crude oil or 10 mL/kg of peanut oil (vehicle control) daily for 15 days. We found that birds receiving the highest dosage experienced a significant increase in reticulocyte percentage, mean corpuscular hemoglobin concentration, and liver mass, as well as inflammation of the gastrointestinal tract and lymphocyte proliferation in the spleen. However, we found no evidence of Heinz body formation based on both light and transmission electron microscopy. Although there was a tendency for packed cell volume and hemoglobin to decrease in birds from the high dose group compared to control and low dose groups, the changes were not statistically significant. Our results indicate that additional experimental dosing studies are needed to understand factors (e.g., dose- and species-specific sensitivity) and confounding variables (e.g., dispersants) that contribute to the presence and severity of anemia resulting from oil exposure in birds.
اظهر المزيد [+] اقل [-]Evaporation rates and pollutants emission from heated cooking oils and influencing factors
2020
Adeniran, Jamiu Adetayo | Yusuf, Rafiu Olasunkanmi | Abdulkadir, Mariam Oyinkansola | Yusuf, Muhammad-Najeeb O. | Abdulraheem, Khadija Abdulkareem | Adeoye, Babatunde Kazeem | Sonibare, Jacob Ademola | Du, Mingxi
The heating of edible oils during cooking activities promotes the emissions of pollutants that have adverse impacts on the health of humans. This study investigated the evaporative emissions of fifteen (15) commonly used cooking oils. Split-plot experimental design under the response surface methodology framework was used to study singular and interaction effects of influencing parameters (temperature, volume of cooking oil and time) on cooking oil evaporation rate and pollutants emissions (i.e. Particulate matter of aerodynamic diameter ≤1 μm (PM₁.₀); ≤2.5 μm (PM₂.₅); ≤10 μm (PM₁₀); Total Suspended Particulate (TSP); Total Volatile Organic Compounds -TVOCs, and Carbon Monoxide- CO) on a groundnut oil sample that served as a case study. Obtained values of density, viscosity, kinematic viscosity, smoke, flash and fire points were; 873–917 kg/m³; 1.12–9.7 kg/ms; 2.4–3.4 m²/s; 96 -100 °C; 124–179 °C and 142–186 °C, respectively. The role of temperature as the most significant parameter influencing the rate of evaporative emissions was established. Evaporation rate and pollutants emission from unrefined samples were the highest. The restricted maximum likelihood (REML) analysis results suggested a strong relationship between the actual values and the predicted values as R-squared values obtained were greater than 0.8 for all the responses. These results suggest that minimal rates of evaporation and pollutants emission from heating cooking oils can be achieved with a high volume of the cooking oil at moderate temperature levels.
اظهر المزيد [+] اقل [-]Electrospun PS/PAN fibers with improved mechanical property for removal of oil from water
2015
Li, Peng | Qiao, Ying | Zhao, Lili | Yao, Dahu | Sun, Haixiang | Hou, Yingfei | Li, Shuo | Li, Qi
A mechanically robust and high-capacity oil sorbent is prepared by electrospinning a blend of polystyrene (PS) and polyacrylonitrile (PAN). The morphology, oil sorption capacity and mechanical property of the fibers formed in different compositions are investigated in detail. It is shown that the oil sorption capacity is a result of both the chemical composition and the specific surface area which related to diameter size. The addition of PAN as a component in fibrous sorbents can significantly improve the mechanical properties of PS fibers. Moreover, the oil sorption capacity increases with decreasing fiber diameter. The results also show that the maximum sorption capacities of the PS/PAN sorbent for pump oil, peanut oil, diesel, and gasoline were 194.85, 131.70, 66.75, and 43.38gg−1, respectively. Additionally, the sorbent exhibits quick oil sorption speed as well as high buoyancy, which make it a promising candidate for use as an oil spill cleanup sorbent.
اظهر المزيد [+] اقل [-]A novel hydroxofluorographene-coated melamine foam for efficient and repeatable oil removal from water
2020
Zhou, Xinyi | Li, Yi | Zhang, Chi | Wang, Yuming | Lu, Yumiao
With the frequent occurrence of oil spill accidents and the continuous discharge of oily water during oil production and transportation, effective oil removal from environmental water by adsorption still faces severe challenges. Here, a novel absorbent hydroxofluorographene-coated melamine foam, namely G(OH)F@MF, with high affinity to oils was fabricated via stepwise assembly. The G(OH)F@MF absorbent achieved effective removal of various oils within 1 min with relatively high adsorption capacities for petrol (89.34 g/g), lubricating oil (89.60 g/g), and peanut oil (104.79 g/g). Furthermore, it could be regenerated by simply squeezing and reused for more than 10 times with an adsorption capacity exceeding 37.12 g/g. In addition, the results indicated that the G(OH)F@MF absorbent was suitable for oil cleanup at a wide range of pH values (4–12) and temperatures (5–45 °C). The adsorption performance of the material was stable in the presence of natural organic matter and even in different water environments. This study can provide a novel sorbent and method for the green, rapid, recyclable, and stable removal of oils from environmental water.
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